We (Southwest people) always go to Corcoran's Irish Pub (between Gate C1 and C2). Relaxing, good wine, and drinks. Rarely crowded since it's down at the end of the concourse. A great place to wait and relax, maybe use the wi-fi. Pre-prepared sandwiches are very ok, and are so thick you can split one. Bathrooms nearby (gate C1), but they are small. Don't wait until Gate C1 is de-planeing.
Jersey Mike's Subs is very good too, but usually has a long line. But not as good as Sam's Town Sports Deli, which you can order (back at Sam's Town) before you leave for the airport. They will pack them up to go. This is the whole reason for staying at Sam's Town on your last night on Las Vegas. Chips included.
- bcc